Chiyomi is a teenage girl. She has gray eyes and medium-short dirty blonde hair with a light-yellow headband in it. She also appears to have a light-yellow bow on the back of her head. Chiyomi wears the Minazuki Academy High School's uniform - a light beige shirt tied with a blue bow around the collar, a dark-colored skirt, black tights and black shoes.
Chiyomi has been friends with Ayame Itou since elementary school. A boisterous, energetic girl with a strange vocabulary, her classmates all unanimously nicknamed her "No Filter." When Chiyomi went to visit Ayame in the Amare Patriarcha Crucis hospital, she invited her classmates to come along with her. 
Ayame and Ritsuko Satomi find Chiyomi being attacked by a zombie. Ayame then frees her by hitting the zombie with a nearby crutch. Chiyomi decides to travel with them; however, Chiyomi leaves the group shortly after having a heated argument with Ritsuko. She is later shown captured by a SWAT team.